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Why don’t marine mammals like whales get “the bends”? (continued)
John Davies
Lancaster, UK
A previous correspondent explained why whales don’t get the bends, and went on to describe how the bends were first encountered as caissons disease, ascribing this to deep hard rock mining. He was wrong.
Air pressure varies by about 0.8 kilopascals per 1000 metres. The world’s deepest mine, Mponeng gold mine in South Africa, stretches to around 4000 metres below the surface, so the pressure at the bottom would be 104 kPa, rather than the 101 kPa at sea level (although the mine entrance is…
